What You Need
to Know About
Urinalysis
A urinalysis is a simple, inexpensive test that can
help to detect problems in many parts of your
body including your kidneys and urinary tract, your
heart and your liver. A urinalysis can help to detect
many diseases before symptoms occur. Early detection
and treatment can often prevent serious diseases
from getting worse. More than 20 million
Americans—one in nine adults—have chronic kidney
disease, and most don’t even know it. More
than 20 million others are at increased risk for
chronic kidney disease. Yet, a urinalysis can detect
protein in the urine—one of the earliest signs of
kidney disease—years before symptoms appear
and at a time when treatment can make all the
difference.
What is a urinalysis?
A urinalysis is an examination of a sample of
urine that can help find medical problems like
kidney disease, diabetes, liver disease and urinary
tract infections.
Who should have a urinalysis?
Everyone should have a urinalysis as a child and
then periodically as an adult. It’s especially important
for people who have an increased risk for kidney
disease to be tested for protein in their urine.
This is included in a urinalysis. Persistent protein in
the urine (two positive tests for protein over several
weeks) is one of the earliest signs of chronic kidney
disease. You may be at increased risk for kidney
disease if you:
❖ have diabetes
❖ have high blood pressure
❖ have a family history of chronic
kidney disease
❖ are an older adult
❖ are an African American, Hispanic
American, Asian or Pacific Islander or
American Indian.
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If you have any of these risk factors, or think you
may be at increased risk for chronic kidney disease,
speak to your doctor about having a urinalysis.
What does a urinalysis include?
A urinalysis has three parts:
1. Visual examination of the urine sample for
color and clearness. Blood may make urine look
red or the color of tea or cola. An infection may
make urine look cloudy.
2. A dipstick examination, which uses a chemically
treated strip to check for the following:
❖ pH is a measure of the amount of acid in the
urine. An abnormal pH may be a sign of kidney
stones, urinary infections, chronic kidney
disease or certain disorders that affect growth
and development in children.
❖ Protein is an important building block in the
body. When your kidneys are damaged, protein
leaks into your urine. Persistent protein in
protein in the urine suggests that the kidney’s filteringunits have been damaged by chronic kidney disease.
❖ Urine Creatinine gives an estimate of the
concentration of your urine, which allows for
a more accurate protein result. Creatinine is a
by-product of normal muscle activity, which is
found in the urine and blood.
❖ Glucose (sugar) is usually a sign of diabetes.
In children, sugar in the urine may sometimes
be related to a disorder that affects growth
and development.
❖ Bacteria and white blood cells (pus cells) are
signs of infection. Bacteria without white
blood cells may suggest another type of problem
such as vaginal or bladder disease.
❖ Bilirubin is a waste product from the breakdown
of old red blood cells. It is normally
removed from the blood by the liver and
becomes part of bile. Its presence in the urine
may be a sign of a liver disease.
3. Urinalysis also includes examining a small amount
of urine under a microscope. Some of the things
that may be seen include:
❖ Red blood cells, which may be a sign of kidney
diseases that damage the filtering units of
the kidneys, allowing blood cells to leak into
the urine. Blood in the urine may also be a
sign of problems like kidney stones,
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infections, bladder cancer or a blood disorder
like sickle cell disease. While enough
blood may be present to cause a color
change you can see, blood in the urine is
usually so small that a microscope is needed
to see it.
❖ White blood cells (or pus cells), which are a
sign of an infection or inflammation in the
kidneys, bladder or another area.
❖ Bacteria, or germs, which are usually a sign
of an infection in the body.
❖ Casts, which are tube-shaped forms made
of protein, and may have red or white blood
cells or other cells inside. Casts form in certain
kidney diseases because the kidneys are
releasing a sticky type of protein that traps
blood cells and other types of cells.
❖ Crystals, which are formed from chemicals
in the urine. If they become large enough,
they form kidney stones.
How is a urinalysis done?
Your urine is collected in a clean specimen cup.
Some of the urine sample is tested right away with
a dipstick. The rest is placed in a test tube and
spun before being checked under the microscope.
Only a small amount of your urine is needed
(about 2 tablespoonfuls) to do the test. If possible,
your morning urine is the best, but a random
sample can also be used. The urine should be as
fresh as possible and, therefore, should not be
brought from home.
Can any drugs or vitamins
affect my results?
Yes, many drugs and vitamins can affect the urinalysis.
For example, vitamin C pills, antibiotics and
certain drugs used to treat Parkinson’s disease
could cause you to have a “false” positive result,
and you may need to have other tests to confirm
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your result. Make sure to tell your doctor or clinic
staff about all the medications and vitamins
you take. Fever and heavy exercise can also give
false results.
Is a urinalysis expensive?
How long does it take to get
my results?
A urinalysis is a simple, inexpensive test. Most
insurance carriers cover part or all of a urinalysis
test. A urinalysis can be done right in your doctor’s
office. The test takes only about 5 to 10
minutes to do, and you can discuss your results
with your doctor right away. A urinalysis can also
be done in a laboratory.
What does it mean if my urine
test shows protein and/or blood?
You may have kidney or urinary tract disease,
but your doctor will need to confirm this.
Persistent protein in the urine (two positive results
over several weeks) is a sign of chronic kidney disease.
Your doctor may do the following tests to
confirm your diagnosis, check your kidney function
and help plan your treatment:
❖ A simple test for creatinine in your blood,
which can be used to estimate how much kidney
function you have (see glomerular filtration
rate). Creatinine is a by-product that comes
from normal muscle activity. When your kidneys
are damaged, your blood creatinine level may
build to a high level.
❖ Glomerular filtration rate (GFR), which tells
your doctor how much kidney function you
have. You do not need another test to check
your GFR. Your doctor can calculate your GFR
from your blood creatinine test, your age, gender
and body size. Your GFR is the best way to
track your kidney function.
❖ An ultrasound or CT scan, which gives your
doctor a picture of your kidneys and urinary
tract. This shows whether your kidneys are too
small or too large or have kidney stones,
tumors or other problems.
❖ A kidney biopsy, which is done in some cases
to help identify a specific type of kidney disease
and see how much kidney damage has
occurred. To do the biopsy, the doctor removes
small pieces of kidney tissue and looks at them
under a microscope.
If my tests show kidney or
urinary tract disease, what treatment
will I need?
Your treatment plan is based on the type of kidney
or urinary tract disease you have, your level of kidney
function and other health problems you may
have. Some diseases can be treated with medications.
Others could require surgery. If severe kidney
disease is found, dialysis or a kidney trans-plant
may be needed.
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Can treatment prevent
chronic kidney disease from getting
worse?
Yes. In many cases, early detection and treatment
may keep chronic kidney disease from getting
worse.
How can a urinalysis
help to detect early signs of
heart disease?
Studies show that people who have protein in
their urine have an increased chance of developing
heart disease as well as kidney disease. Many
health problems that affect the kidneys, such as
diabetes and high blood pressure, also affect the
heart and blood vessels. Protein in the urine may
be a sign that the blood vessels have already been
damaged by these diseases, and organs such as
the heart and kidneys have been affected.
This brochure was supported by an educational grant from
National Kidney Foundation
30 East 33rd Street
New York, NY 10016
800-622-9010
www.kidney.org
© 2002 National Kidney Foundation, Inc.
All Rights Reserved. No part of this publication may be reproduced or transmitted
in any form or by any means, electronic or mechanical, includ-ing
photocopy, recording or any information storage and retrieval system, without
permission in writing from the National Kidney Foundation, Inc.
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